Prolonged persistence of Listeria monocytogenes after intragastric infection in corticosteroid-treated mice.
In an attempt to obtain a model more closely resembling natural listeriosis, we studied the course of infection in mice inoculated by the intragastric route with Listeria monocytogenes. Corticosteroid-treated, and untreated mice both developed subclinical infection without mortality, but faecal shedding and persistence of bacteria in the liver and spleen of corticosteroid-treated mice were significantly more protracted than in untreated mice. Untreated mice cleared the bacteria from their livers and spleens by day 5 postinfection (PI), whereas treated mice did not clear the organisms until 8-9 days PI. In untreated mice faecal shedding lasted 5 days PI, whereas in treated mice the organisms were recovered at significantly higher levels until day 9 PI. The only intestinal lesions observed were mild pyogranulomatous changes in the dome area of some Peyer's patches in treated mice.
Prats
N
N
Departamento de Patología y Producciones Animales (Anatomía Patológica), Facultad de Veterinaria, Universidad Autónoma de Barcelona, Bellaterra, Spain.
López
S
S
Domingo
M
M
Briones
V
V
García
J A
JA
Domínguez
L
L
Marco
A J
AJ
D000818:Animals; D015169:Colony Count, Microbial; D003907:Dexamethasone / Q000494:pharmacology*; D004195:Disease Models, Animal; D005243:Feces / Q000382:microbiology; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology*; D007150:Immunohistochemistry; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000302:isolation & purification / Q000472:pathogenicity; D008088:Listeriosis / Q000382:microbiology* / Q000473:pathology; D008099:Liver / Q000382:microbiology / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D051379:Mice; D010581:Peyer's Patches / Q000473:pathology; D013154:Spleen / Q000382:microbiology / Q000473:pathology
D005938:Glucocorticoids; D003907:Dexamethasone